NEET-PG 2015 - Anatomy Practice Questions

Q: Inferior pancreaticoduodenal artery is a branch of which of the following arteries?

Superior mesenteric artery. ***Superior mesenteric artery*** - The **inferior pancreaticoduodenal artery** is a direct branch of the **superior mesenteric artery (SMA)**. - It supplies the **head of the pancreas** and the **duodenum**, anastomosing with branches from the gastroduodenal artery. *Splenic artery* - The splenic artery is a branch of the **celiac trunk** and primarily supplies the **spleen**, stomach, and pancreas (via pancreatic branches). - It does not give rise to the inferior pancreaticoduodenal artery. *Left gastric artery* - The left gastric artery is a branch of the **celiac trunk** and supplies the **lesser curvature of the stomach** and distal esophagus. - It has no direct connection to the inferior pancreaticoduodenal artery. *Gastroduodenal artery* - The gastroduodenal artery is a branch of the **common hepatic artery** (from the celiac trunk) and gives off the **anterior and posterior superior pancreaticoduodenal arteries**. - While it supplies the head of the pancreas and duodenum, it is not the origin of the inferior pancreaticoduodenal artery, which arises from the SMA.

Q: Which of the following is NOT a boundary of the foramen of Winslow?

4th part of Duodenum. 4th part of Duodenum[1] - The foramen of Winslow (epiploic foramen) is an opening that connects the greater sac to the lesser sac of the peritoneum. The 4th part of the duodenum is not a boundary of this foramen. - The 4th part of the duodenum is located at the duodenojejunal junction on the left side of the abdomen, far from the foramen of Winslow. - Note: The 1st part of the duodenum (D1) forms the inferior boundary of the foramen of Winslow, along with the hepatic artery. Inferior vena cava[1] - The inferior vena cava (IVC) forms the posterior boundary of the foramen of Winslow. - It lies behind the peritoneum that forms the posterior wall of the lesser sac at this point. Free border of lesser omentum[1] - The free border of the lesser omentum (hepatoduodenal ligament) forms the anterior boundary of the foramen of Winslow. - This ligament contains the portal triad (hepatic artery proper, portal vein, and common bile duct). Caudate lobe of liver[1] - The caudate lobe of the liver forms the superior boundary of the foramen of Winslow.[1] - It lies above the opening, contributing to its roof.

Q: The Great cerebral vein of Galen drains into which structure?

Straight sinus. ***Straight sinus*** - The **Great cerebral vein of Galen** is a major venous channel that collects blood from the deep cerebral veins, including the internal cerebral veins. - It empties directly into the **straight sinus**, which then joins the confluence of sinuses. *Cavernous sinus* - The **cavernous sinus** drains blood from the orbit, face, and temporal lobe, and it receives input from superficial cerebral veins, not the deep system of Galen. - It is located on either side of the **sella turcica** and is distinct from the drainage pathway of the Great cerebral vein. *Basal vein of Rosenthal* - The **basal vein of Rosenthal** is a tributary that drains into the Great cerebral vein of Galen, not a structure that Galen drains into. - It courses around the midbrain and receives blood from various deep structures, eventually contributing to the formation of the Great cerebral vein. *Internal cerebral vein* - The **internal cerebral veins** are tributaries that merge to form the Great cerebral vein of Galen; therefore, Galen does not drain into them. - These veins run within the tela choroidea of the third ventricle and collect blood from the thalamus, basal ganglia, and internal capsule.

Q: What is the characteristic upper limb deformity seen in Erb's palsy?

Adduction and medial rotation of arm. ***Adduction and medial rotation of arm*** - Erb's palsy, resulting from injury to the **upper brachial plexus** (C5-C6 nerve roots), primarily affects the **deltoid**, **supraspinatus**, **infraspinatus**, and **biceps** muscles. - The unopposed action of unaffected muscles, such as the **pectoris major** and **latissimus dorsi**, leads to the characteristic **waiter's tip position**, involving **adduction** and **medial rotation** of the arm. *Adduction and lateral rotation of arm* - This position would imply weakness of the **pectoralis major** and **latissimus dorsi** and stronger activity of the **infraspinatus** and **teres minor**, which is contrary to the muscle deficits in Erb's palsy. - **Lateral rotation** of the arm is typically impaired in Erb's palsy due to weakness of the **infraspinatus** and **teres minor**. *Abduction and lateral rotation of arm* - **Abduction** is severely impacted in Erb's palsy due to paralysis of the **deltoid** and **supraspinatus**. - This position would suggest intact function of muscles that are explicitly weakened or paralyzed in Erb's palsy. *Abduction and medial rotation of arm* - While **medial rotation** can be a component of the deformity, **abduction** is a movement that is significantly impaired in Erb's palsy, making this option incorrect. - The inability to abduct the arm is a hallmark of the condition due to weakness of the **deltoid** and **supraspinatus**.

Q: Which structure forms the lateral border of the ischiorectal fossa?

Obturator internus muscle. ***Obturator internus muscle*** - The **ischiorectal fossa** (also known as the **ischioanal fossa**) is a wedge-shaped space in the perineum, and its lateral wall is formed by the **obturator internus muscle** and its covering fascia [1]. - This muscle originates from the inner surface of the **obturator membrane** and the surrounding bone, descending through the lesser sciatic foramen to insert on the greater trochanter of the femur. *Perineal membrane* - The **perineal membrane** is a dense fibrous sheet that forms the inferior boundary of the **deep perineal pouch**. - It does not form a lateral border of the ischiorectal fossa but rather contributes to the floor of the **urogenital triangle**, anterior to the fossa. *Gluteus maximus* - The **gluteus maximus** is a large muscle of the buttock, primarily involved in extension and lateral rotation of the hip. - It lies superficial to the structures of the perineum and therefore does not form a boundary of the **ischiorectal fossa**. *Sacrotuberous ligament* - The **sacrotuberous ligament** is a strong fibrous band connecting the sacrum to the ischial tuberosity. - While it helps to define the boundaries of the **perineum** posteriorly and contributes to the stability of the **sacroiliac joint**, it does not form the lateral wall of the **ischiorectal fossa**.

Q: Oculomotor nucleus is located in -

Midbrain. ***Midbrain*** - The **oculomotor nucleus** (cranial nerve III) and the Edinger-Westphal nucleus (parasympathetic component) are both located in the **ventral gray matter** near the cerebral aqueduct in the **midbrain** [1]. - This position allows the oculomotor nerve to exit from the interpeduncular fossa of the midbrain [1]. *Forebrain* - The **forebrain** primarily contains structures like the cerebral hemispheres, thalamus, and hypothalamus, which are involved in higher cognitive functions and sensory processing. - No cranial nerve nuclei are located within the forebrain itself; they are largely concentrated in the brainstem. *Pons* - The **pons** contains nuclei for cranial nerves V (trigeminal), VI (abducens), VII (facial), and VIII (vestibulocochlear), but not the oculomotor nucleus. - It is located inferior to the midbrain and superior to the medulla. *Medulla* - The **medulla oblongata** houses nuclei for cranial nerves IX (glossopharyngeal), X (vagus), XI (accessory), and XII (hypoglossal). - It is the most caudal part of the brainstem, inferior to the pons, and is not where the oculomotor nucleus is found.

Q: Which are the segments of the upper lobe of the right lung?

Apical, anterior, posterior. ***Apical, anterior, posterior*** - The **right upper lobe** is consistently divided into three bronchopulmonary segments: **apical**, **anterior**, and **posterior** [1]. - These segments are named according to their anatomical position and the branching of the **tertiary bronchi** that supply them [1]. *Anterior, posterior, medial* - While **anterior** and **posterior** segments exist, the "medial" segment is not a standard division of the right upper lobe. - The term "medial" is typically associated with the **middle lobe** of the right lung (medial and lateral segments) [1]. *Lateral, medial, superior* - The segments **lateral** and **medial** are characteristic of the **right middle lobe** [1]. - "Superior" is a general directional term and not a specific segment name within the upper lobe in this context, although the apical segment is superiorly located. *Basal, medial, lateral* - **Basal** segments are found in the **lower lobes** of the lungs (e.g., anterior basal, medial basal, posterior basal, lateral basal). - **Medial** and **lateral** segments are typical of the **right middle lobe**, not the upper lobe [1].

Q: Which tract is responsible for the ventral tegmental decussation in the cerebral peduncle?

Rubrospinal tract. The rubrospinal tract originates in the red nucleus and decussates in the ventral tegmental decussation at the level of the midbrain, before descending to the spinal cord. This decussation is the characteristic feature that distinguishes it from other descending tracts. It primarily modulates flexor muscle tone and fine motor control of distal limb muscles. The tectospinal tract originates in the superior colliculus and decussates immediately as the dorsal tegmental decussation, involved in coordinating head and eye movements in response to stimuli. The vestibulospinal tract originates in the vestibular nuclei and descends ipsilaterally and contralaterally [1], but it does not form a distinct ventral tegmental decussation in the cerebral peduncle. It is crucial for maintaining posture and balance by influencing extensor muscles [1]. The tectobulbar tract arises from the superior colliculus and projects to cranial nerve nuclei, but it does not undergo the specific ventral tegmental decussation.

Q: Which of the following structures does NOT pass through the deep inguinal ring?

Ilioinguinal nerve. The ilioinguinal nerve typically passes through the superficial inguinal ring but does not travel through the deep inguinal ring [1]. It lies in the inguinal canal, superficial to the spermatic cord in males and the round ligament in females [1]. The spermatic cord in males enters the inguinal canal through the deep inguinal ring [2]. It contains structures like the vas deferens, testicular artery, pampiniform plexus, and nerves. The internal spermatic fascia is a covering of the spermatic cord that originates from the transversalis fascia at the deep inguinal ring [2]. In females, the round ligament of the uterus is the homologous structure to the spermatic cord in males, and it passes through the deep inguinal ring to enter the inguinal canal. It helps maintain the anteversion of the uterus.

Q: Nephron is derived from ?

Metanephros. ***Metanephros*** - The **metanephric mesenchyme**, also known as the **metanephros**, gives rise to the excretory units of the kidney, which are the nephrons. - This mesenchymal tissue differentiates to form the **glomerulus**, Bowman's capsule, proximal and distal convoluted tubules, and the loop of Henle. *Ureteric bud* - The **ureteric bud** originates from the mesonephric duct and forms the collecting system of the kidney, including the ureter, renal pelvis, calyces, and collecting ducts. - It induces the differentiation of the metanephric mesenchyme but does not directly form the nephron itself. *Mesonephric duct* - The **mesonephric duct** (Wolffian duct) is a primitive embryonic structure that gives rise to the ureteric bud and parts of the male reproductive system. - It does not directly form any part of the nephron. *Mesonephros* - The **mesonephros** is a transient embryonic kidney that functions briefly during fetal development. - It degenerates and does not contribute to the formation of the definitive nephrons in the mature kidney.

Question 1

Inferior pancreaticoduodenal artery is a branch of which of the following arteries?

Accepted Answer

Superior mesenteric artery

Answer

Splenic artery

Answer

Left gastric artery

Answer

Gastroduodenal artery

Question 2

Which of the following is NOT a boundary of the foramen of Winslow?

Accepted Answer

4th part of Duodenum

Answer

Inferior vena cava

Answer

Free border of lesser omentum

Answer

Caudate lobe of liver

Question 3

The Great cerebral vein of Galen drains into which structure?

Accepted Answer

Straight sinus

Answer

Cavernous sinus

Answer

Basal vein of Rosenthal

Answer

Internal cerebral vein

Question 4

What is the characteristic upper limb deformity seen in Erb's palsy?

Accepted Answer

Adduction and medial rotation of arm

Answer

Adduction and lateral rotation of arm

Answer

Abduction and lateral rotation of arm

Answer

Abduction and medial rotation of arm

Question 5

Which structure forms the lateral border of the ischiorectal fossa?

Accepted Answer

Obturator internus muscle

Answer

Perineal membrane

Answer

Gluteus maximus

Answer

Sacrotuberous ligament

Question 6

Oculomotor nucleus is located in -

Accepted Answer

Midbrain

Answer

Forebrain

Answer

Pons

Answer

Medulla

Question 7

Which are the segments of the upper lobe of the right lung?

Accepted Answer

Apical, anterior, posterior

Answer

Lateral, medial, superior

Answer

Basal, medial, lateral

Answer

Anterior, posterior, medial

Question 8

Which tract is responsible for the ventral tegmental decussation in the cerebral peduncle?

Accepted Answer

Rubrospinal tract

Answer

Tectospinal tract

Answer

Vestibulospinal tract

Answer

Tectobulbar tract

Question 9

Which of the following structures does NOT pass through the deep inguinal ring?

Accepted Answer

Ilioinguinal nerve

Answer

Spermatic cord

Answer

Internal spermatic fascia

Answer

Round ligament

Question 10

Nephron is derived from ?

Accepted Answer

Metanephros

Answer

Ureteric bud

Answer

Mesonephric duct

Answer

Mesonephros

NEET-PG 2015 — Anatomy